The invention relates to a apparatus and method for monitoring a frame relay network, and more particularly to monitoring the network from a plurality of different locations.
Modern communications networks generally include a multiplicity of paths or links that are interconnected to route voice, video and data, traffic from one location of a network to another. At each location, an interconnect node or office couples a variety of sources and destinations to the network. In some cases, the sources and destinations are incorporated in a private line network that includes a series of offices connected together by leased-lines with switching facilities and transmission equipment owned and operated by the carrier and leased to the user. This type of network is conventionally referred to as a circuit-switching network. Accordingly, a source of one office at one location of the network may transmit to a destination of a second office located at another location in the network through their respective switching facilities.
Frame relay is a transmission scheme which may be employed in the type of circuit-switching network described above. Frame relay is a frame based transmission technique designed to create more efficient wide area networks (WANs) by permitting users to access only the amount of bandwidth they need for a given application. Frame relay is a xe2x80x9cconnection-orientedxe2x80x9d protocol. It establishes a logical connection for the duration of the call and may be implemented as a permanent virtual circuit (PVC) service.
As described above, a frame relay network-provides logical connectivity between geographically distributed devices, using special circuits, which can be multiplexed, over a single access path. A frame relay network may consist of two distinct parts. The first part includes customer sites which have customer premise equipment (e.g., routers, bridges, frame relay access devices) that are connected to a frame relay service. The configuration and management of such devices are the responsibility of the customer. The second portion belongs to the frame relay service provider, which has a network of switches, commonly housed in central offices, and are connected using internodal trunks supplied by the service provider. This network of switches and trunks is typically managed and provisioned by the service provider at their own network""s operation center.
A number of different factors may affect the performance of the frame relay network. In order for a service provider to get an accurate picture of the operation of the network, data must be collected and analyzed from both the first and second portions of the system.
Currently, frame relay service providers offer network services to customers for transmitting information between two geographically separated sites. The frame relay service providers establish a connection between equipment located at the customer""s site and the frame relay network. The inventor has recognized that it may be desirable to monitor the operation of the frame relay network from a plurality of different locations which may include the ingress and egress points of the customer""s equipment as well as at different points within the network itself.
In the system described herein, a connection is established between the customer provided equipment (CPE), which may include routers, bridges, frame relay access devices and the frame relay network. Incorporated into the provided equipment at the customer site are devices and systems for instrumenting inflow and outflow of transmitted information from specified points. In one aspect of the invention, simple network management protocol (SNMP) management information bases (MIBs) are used as part of a management system. Incorporated into customer provided equipment are software modules which employ the SNMP to monitor the ingress and egress of data from the particular site.
In a frame relay system, individual frames are transmitted and received over the frame relay network. The frames are made up of a variety of different elements. Of particular interest are the octets which include identifying information for the frame as well as the data which the system user is trying to transmit. A particular frame may carry as little as two octets or as many as is necessary in order to transmit the, information. The SNMP protocol in conjunction with the MIB may be configured to count the total number of frames received and transmitted as well as the total number of octets. In order to give a system user a better idea of where frames are being dropped in the system, SNMP may be employed to monitor the transmission and receipt of frames at different points in the frame relay network including the customer provided equipment, as well as points within the network itself.
In one aspect of the invention, the customer provided equipment may be connected to the frame relay network over an electrical connection, such as a T1 transmission line. On the customer side, the line may be connected to a customer data terminal equipment (DTE) device such as a router, a bridge or a frame relay access device. Located between the DTE and the transmission line may be an interface device which monitors and controls the magnitude of the signals between the customer provided electronics and the network itself. On the network side, the connection may be made to a public switch.
In one aspect of the invention the customer may wish to monitor the transmission and receipt of frames and octets over the transmission line between the customer equipment and the network. Information is gathered from the frame relay network and the CPE at to the quantities of data transmitted and received. To gather this information, the service provider employs a network, management server, which is programmed to request, process, and analyze information received from the locations being monitored. Among the types of analysis which may be performed, is a comparison may be made between the data (frames and/or octets) originating from the CPE, with the data received at the access port to the frame relay network. An analysis may also be performed of data traveling in the opposite direction.
In yet another aspect of the invention, monitoring processes may be performed for the virtual circuits in the frame relay network. In a frame relay network, a number of virtual circuits may be established between a particular origination point and a number of different destinations. According to the invention described herein, the SNMP may be used to collect data relating to the ingress and egress at origination and destination points within the frame relay network. In order words, monitoring may be performed at the public access switch which establishes the connection with the CPE. Another monitoring point may then be established at the point where the data exits the data network and is delivered to the destination CPE. Further analysis may also be performed from various nodes within the frame relay network to monitoring locations at the CPE""s.
In yet another aspect of the invention, the information gathered during monitoring may be processed such that it is compared against a constant which was generated in light of known operating parameters of the network, or tolerances of a particular customer for dropping frames. This comparison provides an indication of the performance of portions of the system against a known standard.
Numerous modifications and additions will be apparent to those skilled in the art upon further consideration of the invention.